Consolidated Statement of Equity (Parenthetical) - $ / shares	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Shares pursuant to dividend reinvestment plan (in shares)	96,268	83,978
Shares due to exercise of employee stock options and issuance of directors' deferred stock (in shares)	910	11,745
Number of partnership units issued in transaction (in shares)	1,416,071
Limited Partner
Shares pursuant to dividend reinvestment plan (in shares)	19,493	15,101
Dividend Distributions Payable
Distributions payable common stock, per share (in usd per share)	$ 0.53	$ 0.53
Distributions partnership units, per unit (in usd per share)	0.53	0.53
Series D Cumulative Redeemable Preferred Stock \| Dividend Distributions Payable
Distributions payable on preferred stock, per share (in usd per share)	38.28	38.28
Series E Cumulative Redeemable Preferred Stock \| Dividend Distributions Payable
Distributions payable on preferred stock, per share (in usd per share)	$ 37.50	$ 37.50

Aggregate dividends declared during the period for each share of common stock outstanding.

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